Aspirin Lab

This week some of our class did the Aspirin lab. I didn't get to do the lab though, despite memorizing the entire lab packet. Since I did that I'm going to make a blog post about the lab, with data and pictures from the wonderful Meg Tersteeg's lab.

Cutting out filter paper in preparation

1st day of lab:

First you use a weigh boat to measure out 5.00g of Salicylic acid (C7H603 ). Then you transfer it to a 125mL Erlenmeyer flask.
Record this starting mass: 5.1444g

Weigh boat

Then bring the flask under the hood and have 7.00mL of acetic anhydride ( C4H603 ) delivered to the flask. It is important to not let the acetic anhydride to contact your skin or let the vapor get in your eyes, as it is a dangerous acid.

Now add 8 drops of the catalyst, Sulfuric Acid (H2SO4).

Next you heat the starting materials:

Assemble a hot water bath using with a 400, 600, or 800 mL beaker. Do this at your lab bench and place the flask in it. Heat till boiling + an additional 15 minutes

Heating the flask

Lastly for day one, you cool the mixture.

Allow flask to sit on lab bench to cool for about 15 minutes

After, add 15mL of ice cold water to decompose the excess anhydride.

Place flask in ice bath till crystallization of aspirin is complete.

Day two:

Isolate the product-

Collect the solid aspirin using a Buchner funnel and filter paper. Rinse flask twice with 3mL of ice cold water to remove any residual crystals.

Discard leftover filtrate in waste container under the hood.

Buchner funnel set up

Rinsing flask with ice cold deionized water

Lastly in the lab you dry the product by suction filtration.

Dry the crystal by pulling air through them for 15 minutes.

Finished, dried product.

I chose to write about the lab procedure instead of the significance of the lab because I did not get to participate in the lab.